Chlamydia inclusions possess a higher proportion of metabolized TFSM 1 than host cell membranes. HeLa cells were infected with C. trachomatis at a multiplicity of infection (MOI) 1 in the presence of 10 M TFSM 1 and 1% FBS. After 24 h of treatment, cells were fixed, stained with BODIPY-FL-DBCO (backbone) and AlexaFluor TM (AF)546-azide (headgroup), and samples were imaged with a confocal microscope. The metabolic state of TFSM is described by the ratio of 3x Forster resonance energy transfer (FRET) channel vs. donor channel (BODIPY-FL). Chlamydial inclusions are indicated with white circles. n = 5. Scale bars: 10 m, zoomed: 5 m.
